The username must be known to the unix authentication system (usually
/etc/passwd entry). It can have a /bin/false shell and a /dev/null
homedir, and a invalid unix password, if security policy prohibits this
user to log on via telnet/ssh etc.
In fact, the /etc/passwd entry (or winbind mapping or nis+ or whatever
else) is just a means to provide a usable local UID, which will be used
for access control and file ownership validation.
WinXXP error#4711: TCPA/NGSCB VIOLATION: Non-approved partition-id 83 (linux)
discovered. Online-recertification and reactivation of Microsoft products
required, 3 days grace period: http://www.yqcomputer.com/